Magnesium Requirement Calculator

About this calculator

The recommended dietary allowance (RDA) for magnesium varies by age and sex — in the U.S., adult men need roughly 400-420 mg/day and adult women roughly 310-320 mg/day, with slightly higher targets during pregnancy, according to National Institutes of Health Office of Dietary Supplements reference values. Magnesium is a cofactor in more than 300 enzymatic reactions in the body, playing roles in muscle and nerve function, blood glucose regulation, blood pressure regulation, and bone structure, which is why it's tracked as a core micronutrient rather than an optional supplement.

Dietitians and nutrition-tracking apps calculate personalized magnesium targets because population surveys, including U.S. NHANES data, have repeatedly found that a substantial share of adults fall short of the RDA from diet alone, particularly those who eat few magnesium-rich foods like leafy greens, nuts, seeds, and whole grains — a gap worth quantifying since chronically low intake has been studied in connection with muscle cramps, fatigue, and increased cardiovascular risk markers.

This calculator takes your age and sex and returns your recommended daily magnesium intake based on official RDA reference values.